Window sash balance



I), 31, 1957 v E. FOST ER 23 K 2 wmuqw SASH ALANCE Filed Dec.- 15, 1955 V yl INVENTOR EDWIN E. FOSTER X BY X? W? ATTORNEYS United States Patent WINDOW SASH BALANCE Edwin E. Foster, Austin, Tex.

Application December 15, 1955, Serial No. 553,245

1 Claim. (Cl. 16-197) This invention relates to a window sash balance particularly for double-hung windows and metal windows made of aluminum and other metals. The invention is an improvement over the window sash balances disclosed in my prior application filed June 3, 1955, under Serial No. $13,087.

It is an object of the invention to provide a sash balmice which is much narrower in cross section than the stile and frame of the window. It is a further object of the invention to provide a sash balance housing made of one piece and which can be applied to existing windows. A still further object of the invention is to provide a sash balance which can be applied to windows merely by the application of screws to hold the housing of the balance and to secure the end of the spring ribbon.

Another object of the invention resides in the provision of a housing structure for a spring ribbon which is adapted to be secured with screws on a window frame and on a window sash with one end of the spring ribbon mounted by means of a screw, on the window sash or the window frame.

Further objects will be apparent from the following description when considered in connection with the accompanying drawing in which;

Figure 1 is a perspective view of a part of the window showing the sash balance secured to the window sash and to the frame,

Fig. 2 is an end view of the coiled spring,

Fig. 3 is a cross section of the sash balance taken on line 33 of Fig. 4, and

Fig. 4 is a top plan view of the sash balance.

As shown in Fig. 1, that figure shows one side of a part of the window as viewed from the inside of the house and as shown a balance 3 is secured to the top of the bottom sash 4 and a balance 7 is secured to the underside of the window frame or head jam 8. A screw 1 secures the end of the spring 14 from balance 3 to the side frame 2 and it is fastened to the top of the lower sash 4 by means of two screws and 6. These screws pass through holes 15 and 16 in the casing of the balance and the screws securely hold the respective balance in place. The upper sash balance 7 is secured ,to the head jam 6 to the sash stile 12 by means of a screw 13.

If desired, similar sash balances may be provided on the left hand side of the window by merely providing sash balances secured in a manner similar to those as shown for the right side.

As shown in Fig. 3 the coil ribbon spring 17 which 2,817,872 Patented Dec. 31, 1957 is self-coiling as shown in Fig. 2 in the coiled position, I

is enclosed and rotates in a housing part 18 so that the self-coiling spring revolves against the inside of the housing 18. It is, of course, obvious that the spring could also be mounted by other means, such as a spool, not shown, turning on a pin in the center of the spool. The location of the balances in relation to the window frame and the sash is important making it possible to counterweight both the lower and the upper sashes without the necessity of cutting into the frame or sash stile.

As shown in Figs. 3 and 4 the sash balance includes a housing part 18 and an extended tongue part 19 with the latter having the holes 15 and 16 therein and strengthening :cross ribs 20. The tongue portion 19 is actually U-shaped in cross section with side portions 21 and a curved end portion 22 and such portions 21 and 22 strengthen the tongue portion so that the balance casing is rigid throughout.

The balance may be made of any suitable material such as any metal or alloy and may be made of aluminum, zinc, stainless steel, or any other suitable metal or alloy.

The operation of the balance is believed to be obvious from the foregoing description and drawing and as shown in Fig. 1 the balance 7 has the spring completely coiled in its housing whereas the spring in the balance 3 is uncoiled but tension or force in the spring is the same in both positions of the springs. For the lower sash 4 as the latter is raised the spring 14 coils itself in the housing of the balance 3 to counterbalance the weight of the sash. For the upper sash 12 as the latter is lowered the spring from the balance 7 will uncoil so that the operation in both sashes is exactly the same. There is, of course, a constant tension in the spring and as shown in Fig. 3 the spring has a freedom of movement in and out of the housing since the end 23 of the housing 18 is open and the housing ends at 24 as to its periphery thereof.

I claim as my invention:

A sash balance for use on a window comprising a housing having means therein to secure it to the outside of the window frame or to the outside of the sash frame, said housing having an enlarged portion provided with a part circumferential surface and an opening at one end of the enlarged portion, 'a tongue portion integral with the housing and flanged around its periphery and extending from the opposite end of the enlarged portion, a plurality of cross ribs extending across the tongue portion and connected to the flanges around the periphery, said housing being adapted to receive a coiled ribbon spring which rotates on the part-circumferential surface when the window is raised or lowered.

References Cited in the file of this patent UNITED STATES PATENTS 2,635,282 Trammell et al Apr. 21, 1953 2,684,499 Lewis July 27, 1954 2,732,594 Adams Jan. 31, 1956 2,739,344 Dickinson Mar. 27, 1956 OTHER REFERENCES Publication: The Ironmonger, page 139, published October 27, 1888. 

